Clinical, Cytological, Histopathological and Immunohistochemical Features of a T-Zone Lymphoma in a Mixed-Breed Dog

Background: Non-Hodgkin lymphoma are a group of lymphoid neoplasms originated from the proliferation of precursors or mature, T, B and/ or NK lymphocytes. T-Zone lymphoma (TZL) is characterized as an indolent lymphoma due to its slow progression and poor chemotherapy´s response. Dogs affected by this neoplasm may live for many years without clinical signs and are often underdiagnosed. The aim of the present article is report a TZL case in a nine-year old male mixed breed dog, submitted to clinical follow-up and chemotherapy. Case: A nine-year old male mixed-breed dog was presented due to the observation of an increased left mandibular lymph node. The previous cytological examination was suggestive of reactive hyperplasia and histopathological examination, by incisional biopsy, compatible with lymphocytic low-grade lymphoma. Physical examination revealed enlarged and firm left mandibular lymph node and adequate physical condition.A cytological examination was performed in the mandibular and  both popliteal lymph nodes and revealed many small lymphocytes with hyperchromatic chromatin, rarely evident nucleolus and whose cytoplasm often projected in the form of a “hind-mirror” or “comet tail”, compatible with lymphocytic lymphoma (low grade) and suggestive of TZL, in the both lymph nodes. The histopathological and immunohistochemical examination, of the mandibular lymph node, were chosen to confirm the diagnosis. At histopathology it was observed 40% of the sample contained a monotonous cell population, composed by small lymphocytes, with some presenting “hand-mirror” morphology. Two mitotic figures were evidenced per field of high magnification (40x), inferring a low-grade disease. Immunohistochemical analysis revealed neoplastic proliferation with immunolabeling of CD3 lymphocytes and positivity for Ki-67, but negative for CD20, CD79a, CD45, MUM-1 and PAX-5. Although there is no consensus about requirements and treatment´s efficacy, it has been chosen to treat the dog with chlorambucil, because of the elevated Ki-67 value (48%). The patient obtained a free-progression interval higher than 820 days, from the earlier investigations of lymphadenopathy, with excellent quality of life and no side effects related to the use of chlorambucil. Discussion: Although TZL is a common subtype of lymphoproliferative disease in dog, it is still underdiagnosed. The TZL diagnosis can be suggested by cytology, from the disclosures in neoplastic cells of a cytoplasmic projections, recognized as a “hand-mirror” or “comet tail”, corroborated with the present case, however the histopathology is confirmatory. Immunohistochemistry in which the neoplasm cells showed a positive immunolabeling for CD3 and negative for CD79a, CD20, CD45, MUM1 and PAX5, as evidenced in this report, confirming the T-cell origin. According to the literature, lymphomas composed by small clear cells and cytoplasm projecting by cytology, immunolabeling CD3 and CD25 positive and CD45 negative are, together, findings that confirmed TZL. The biological behaviour of indolent lymphoma is still largely unknown, however the prognosis of dogs, with indolent lymphoma of T or B cells, seems to be favourable.  Studies showed different days of median overall survival, such as 760 days and 4.4 years. In the present case, the dog showed 820 days, confirming the good prognosis and an indolent behavoiur. Aggressive chemotherapy protocols are not necessary for such cases and the treatment with chlorambucil, without the association of prednisolone, has been well tolerated by the patient, which showed no side effects until the moment

Efeitos do uso tópico do óleo de andiroba puro e ozonizado em feridas induzidas em cavalos

Este trabalho realizou uma avaliação clínica e histopatológica da aplicação tópica do óleo de andiroba (Carapa guianensis Aublet), puro e ozonizado, no processo de cicatrização de feridas em cinco equinos saudáveis. Oito feridas de 6,25 cm2 foram induzidas cirurgicamente, quatro de cada lado da região lombar, craniais em relação à região sacral. Em três animais, o lado esquerdo foi destinado à avaliação macroscópica e mensuração de área, enquanto o lado direito foi destinado à análise histopatológica. Nos outros dois animais, as avaliações foram invertidas. O tratamento tópico foi iniciado 12 horas após a indução cirúrgica e foi mantido diariamente até a completa cicatrização das feridas. Foram usados, sequencialmente e bilateralmente, no sentido craniocaudal: solução salina (GC), solução salina ozonizada (GO), óleo de andiroba puro (GAP) e óleo de andiroba ozonizado (GAO). Aleatoriamente, a sequência de tratamentos foi modificada. As análises macroscópicas e microscópicas foram realizadas 3, 7, 14 e 21 dias após a cirurgia, e o tempo total para cicatrização registrado. A contração da ferida foi de 67,75% para GC, 65,26% para GO, 67,91% para GAP, e 69,84% para GAO. A avaliação histopatológica demonstrou que as feridas tratadas com GAO e GAP apresentaram uma avançada epitelização, proliferação fibroblástica e deposição de colágeno, moderada proliferação vascular e presença de infiltrados de células polimorfonucleares (PMN) e discreta proliferação de células mononucleares (MN). Foi possível concluir que todos os tratamentos usados foram benéficos perante o grupo de controle, mostrando que as versões pura e ozonizada do óleo de andiroba representam alternativas terapêuticas ao tratamento de feridas em equinos.The aim of this study was to evaluate clinical and histopathological aspects of topical application of pure and ozonized andiroba oil (Carapa guianensis Aublet.) on the healing process of wounds of healthy horses. Eight 6.25-cm2 wounds were surgically produced on each horse, cranial to the sacrum, being four wounds on each side of the lumbar region. In three animals, left side was used for macroscopic observations and area measurement and right side was used for histopathological analysis. For the other two animals, evaluations were inverted. Beginning of the topical treatment occurred 12 hours after surgical induction of the injuries and was maintained daily until complete healing of the wounds, using sequentially and bilaterally in the craniocaudal direction saline solution (GC), ozonized saline solution (GO), pure andiroba oil (GAP) and ozonized andiroba oil (GAO). Randomly, sequence of the treatments was modified. Macroscopic and histopathological analyses were performed at 3, 7, 14, and 21 days after surgery. Completed healing time for all wounds were recorded. A wound contraction of 67.75% for GC, 65.26% for GO, 67.91% for GAP, and 69.84% for GAO were recorded. Histopathologic evaluation revealed that wounds from the GAO and GAP had an advanced epithelialization, fibroblast proliferation and collagen deposition, moderate vascular proliferation, and presence of PMN infiltrate and discrete viewing of MN. It was possible to conclude that all treatments had benefits when comparing to control group and both pure and ozonized andiroba oil can be good options for wound treatment in horses

Photobiomodulation as a treatment in dogs with black hair follicular dysplasia: Fotobiomodulação como tratamento para displasia folicular do pêlo preto

Non-inflammatory alopecia can affect animals at any age, but it is necessary to rule out other skin diseases, endocrinopathies and neoplasms, and when diagnosed there is no definitive and standardized treatment, thus the objective is to try to repilate the patient with integrative therapy. Canine patient treated in the dermatology sector at a veterinary clinic in Espírito Santo, with alopecia, hypotrichosis and desquamation all over the body where it has black fur. As a treatment with EccoVet ® equipment, photobiomodulation was performed using red light at a power of 2 joules with follicular growth effect, and blue and green light with an action equal to red light, but adding the effect of shine and softness on the coat and skin hydration, being performed just one weekly session. As a result, the patient started to repilate soon after the first session and achieved total improvement after five sessions. It is concluded that photobiomodulation promotes follicular growth of alopecia in dogs, provided that the protocol indicated for each situation is chosen, in a fast, non-invasive and practical way

Solitary Osseous Plasmacytoma of a Lumbar Vertebrae with Systemic Involvement in a Dog

Background: Myeloma-related disorders are characterized by proliferation of neoplastic plasma cell or immature immunoglobulin secreting B-lymphocytes, and include multiple myeloma, M-macroglobulinemia and extra-medullary plasmacytoma (cutaneous or extra-cutaneous). Solitary osseous plasmacytoma (SOP) is considered an unique entity among extra-medullary extra-cutaneous plasmacytoma. It is an unusual neoplasia in dogs, predominantly found in middle-aged to older animals, with a higher incidence in bones of axial skeleton. Dogs with vertebral SOP present neurological signs related to spinal cord compression, but progression to multiple myeloma is related to a poor outcome. As in humans, progression to multiple myeloma occurs in most cases, although it may take months or years from its initial presentation. SOP´s biological behaviour, incidence and prognostic are rarely documented. Chemotherapy with melphalan and prednisolone represent the most used protocol for multiple myeloma. However, in SOP, the combination of chemotherapy with local approaches is controversial before the evidence of systemic disease. This paper aims at reporting a case of SOP in a lumbar vertebrae of a dog, with systemic involvement. Case: A 11-year old male mixed breed dog was attended presenting muscle weakness, lethargy, anorexia, adipsia and intense pain manifestation. The dog also presented multiple skin nodules, previously diagnosed as a plasmacytoma, through cytology. The dog´s poor clinical condition and aggressive temper, associated with suspicious of an advanced myeloma-related disorder, resulted in the decision for humanized euthanasia. At necropsy, a pale, friable and hemorrhagic mass was identified on the L3 lumbar vertebrae, associated with an osteolytic bone lesion and spinal cord compression. Histopathological analyses revealed proliferation of plasma cells, with pale perinuclear halo, moderate cellular pleomorphism, 10 binucleated cells and 10 mitotic figures per 10 high power fields, compatible with extramedullary plasmacytoma of the mature type, in the lumbar vertebrae (SOP). It was also seen myeloma-related lesions in the skin and subcutaneous, prostate, heart, superficial mandibular and axillary lymph nodesDiscussion: Solitary osseous plasmacytoma is a myeloma-related disorder rarely reported in dogs. Its biological behaviour is poorly characterized, however progression for multiple myeloma is common in humans and dogs, and it is related to a poor outcome. As the present report, systemic progression of SOP has been previously described and although an overt bone marrow infiltration was not detected, such possibility can not be excluded, once multiple myeloma distribution in the bone marrow is often multifocal. Although chemotherapy is the treatment of choice for multiple myeloma, its indication for SOP is conditioned to the evidence of systemic disease. It might delay tumour progression, but its early implementation may favor the selection of resistant neoplastic clones, making it ineffective when progression to multiple myeloma occurs. In humans radiotherapy is the treatment of choice for SOP, however it may be indicated in association to surgery. A retrospective study showed a higher survival rate in patients with SOP in the axial skeleton, which received surgical treatment combined with radiotherapy, if compared to those treated with surgery or radiotherapy alone. Decision for euthanasia was made based on the suspicious of advanced myeloma-related disorder, patient´s medical condition and aggressive temper, which limited diagnostic investigation and treatment

Effects of topical application of pure and ozonized andiroba oil on experimentally induced wounds in horses

The aim of this study was to evaluate clinical and histopathological aspects of topical application of pure and ozonized andiroba oil (Carapa guianensis Aublet.) on the healing process of wounds of healthy horses. Eight 6.25-cm2 wounds were surgically produced on each horse, cranial to the sacrum, being four wounds on each side of the lumbar region. In three animals, left side was used for macroscopic observations and area measurement and right side was used for histopathological analysis. For the other two animals, evaluations were inverted. Beginning of the topical treatment occurred 12 hours after surgical induction of the injuries and was maintained daily until complete healing of the wounds, using sequentially and bilaterally in the craniocaudal direction saline solution (GC), ozonized saline solution (GO), pure andiroba oil (GAP) and ozonized andiroba oil (GAO). Randomly, sequence of the treatments was modified. Macroscopic and histopathological analyses were performed at 3, 7, 14, and 21 days after surgery. Completed healing time for all wounds were recorded. A wound contraction of 67.75% for GC, 65.26% for GO, 67.91% for GAP, and 69.84% for GAO were recorded. Histopathologic evaluation revealed that wounds from the GAO and GAP had an advanced epithelialization, fibroblast proliferation and collagen deposition, moderate vascular proliferation, and presence of PMN infiltrate and discrete viewing of MN. It was possible to conclude that all treatments had benefits when comparing to control group and both pure and ozonized andiroba oil can be good options for wound treatment in horses

Epidemiology of Canine Mammary Gland Tumours in Espírito Santo, Brazil

Background: Breast tumours represent about 50 to 70% of all neoplasms in female dogs and their occurrence is directly related to the reproductive status and patient´s age. The purpose of this research was to apply the Brazilian consensus on diagnosis, prognosis and treatment of canine mammary tumours and to and define the regional epidemiological aspects of canine mammary gland tumours in Vitoria metropolitan region (ES, Brazil) between 2012 and 2016 and to correlate the macroscopic characteristics such as lesion size and location of the neoplasm with histopathological diagnosis, tumours grade and lymph node metastasis.Materials, Methods & Results: Data were collected from the archives of the Laboratory of Animal Pathology of UVV and the clinical files of the patients seen in the Veterinary Hospital Prof. Ricardo Alexandre Hippler in 5 years (2012 to 2016). The animals were separated into groups by age to facilitate classification in the group with the highest occurrence of neoplasms. The evaluation of the macroscopic characteristics was performed through the histopathological record described in the pathology laboratory, for each patient, at the time of the initial evaluation. After descriptive analysis, data was correlated using Spearmann test, and frequency dispersion was evaluated using chi-square test, both in the software Graph Pad Prism v. 6.01. This study included 255 bitches and diagnosis of 486 lesions, once 48.6% of the dogs had more than one lesion. 86.8% of lesions were consistent with actual mammary neoplasms, of which 67% were malignant and 20% were benign. Non-neoplastic lesions corresponded to 7.2% of cases and 5.8% were extra-mammary neoplasms, with an increased incidence of lipomas (39.3%) and mast cell tumours (32.1%). Cross-breed dogs represented 26.7% of cases. Poodles (25.5%), Pinschers (9.8%) and Dachshund (4.7%) were overrepresented. Among mammary glands, the most affected with 30.8% and 25.4% were for inguinal and caudal abdominal mammary gland, respectively.Regarding the histopathological grade, 43.7% of the malignant mammary gland tumours were grade I, 40% grade II and 16.2% grade III. The neoplasms smaller than 3 cm in diameter, corresponded to 43.7% malignant neoplasms, of which 75 corresponded to grade I. Those larger or equal to 3-5 cm in diameter corresponded to 22.1% malignant neoplasm, of which 31 corresponded to grade II, and those larger than 5 cm in diameter corresponded to 25.8% malignant neoplasms, of which 34 corresponded to grade II. Macroscopic ulceration was reported in 35/486 neoplasms; of these, 85.7% were malignant. Necrosis was evidenced, microscopically in 11.7% of malignant neoplasms and there was a weak, positive correlation between the occurrence of necrosis and ulceration (P < 0.0001; rs = 0.223), which also correlated with tumour size and histological grade. Of these patients, 24.4% had metastases, and of these, 8.8% presented macroscopic abnormalities in the lymph node. Discussion:Older dogs are at higher risk of developing malignant mammary gland tumour when compared to young bitches, most neoplasms with a histopathological grade III occurred in animals older than 10 years, in agreement with the literature. Age increasing might be related to more biologically aggressive mammary gland tumours. Early neutering is commonly recommended to prevent proliferative abnormalities in the mammary glands, but it has been related to several disorders, and neoplasms, in some breeds. Multiple tumours in more than one mammary gland with different histopathological diagnoses among them, isn’t related to multicentric disease or worse prognosis, as also seen in this survey.Among mammary glands, the inguinal and caudal abdominal are often the most affected,as it was observed in this study; however, no differences were observed in the occurrence of malignant neoplasms, benign or non-neoplastic. Background: Breast tumours represent about 50 to 70% of all neoplasms in female dogs and their occurrence is directly related to the reproductive status and patient´s age. The purpose of this research was to apply the Brazilian consensus on diagnosis, prognosis and treatment of canine mammary tumours and to and define the regional epidemiological aspects of canine mammary gland tumours in Vitoria metropolitan region (ES, Brazil) between 2012 and 2016 and to correlate the macroscopic characteristics such as lesion size and location of the neoplasm with histopathological diagnosis, tumours grade and lymph node metastasis.Materials, Methods & Results: Data were collected from the archives of the Laboratory of Animal Pathology of UVV and the clinical files of the patients seen in the Veterinary Hospital Prof. Ricardo Alexandre Hippler in 5 years (2012 to 2016). The animals were separated into groups by age to facilitate classification in the group with the highest occurrence of neoplasms. The evaluation of the macroscopic characteristics was performed through the histopathological record described in the pathology laboratory, for each patient, at the time of the initial evaluation. After descriptive analysis, data was correlated using Spearmann test, and frequency dispersion was evaluated using chi-square test, both in the software Graph Pad Prism v. 6.01. This study included 255 bitches and diagnosis of 486 lesions, once 48.6% of the dogs had more than one lesion. 86.8% of lesions were consistent with actual mammary neoplasms, of which 67% were malignant and 20% were benign. Non-neoplastic lesions corresponded to 7.2% of cases and 5.8% were extra-mammary neoplasms, with an increased incidence of lipomas (39.3%) and mast cell tumours (32.1%). Cross-breed dogs represented 26.7% of cases. Poodles (25.5%), Pinschers (9.8%) and Dachshund (4.7%) were overrepresented. Among mammary glands, the most affected with 30.8% and 25.4% were for inguinal and caudal abdominal mammary gland, respectively.Regarding the histopathological grade, 43.7% of the malignant mammary gland tumours were grade I, 40% grade II and 16.2% grade III. The neoplasms smaller than 3 cm in diameter, corresponded to 43.7% malignant neoplasms, of which 75 corresponded to grade I. Those larger or equal to 3-5 cm in diameter corresponded to 22.1% malignant neoplasm, of which 31 corresponded to grade II, and those larger than 5 cm in diameter corresponded to 25.8% malignant neoplasms, of which 34 corresponded to grade II. Macroscopic ulceration was reported in 35/486 neoplasms; of these, 85.7% were malignant. Necrosis was evidenced, microscopically in 11.7% of malignant neoplasms and there was a weak, positive correlation between the occurrence of necrosis and ulceration (P < 0.0001; rs = 0.223), which also correlated with tumour size and histological grade. Of these patients, 24.4% had metastases, and of these, 8.8% presented macroscopic abnormalities in the lymph node. Discussion:Older dogs are at higher risk of developing malignant mammary gland tumour when compared to young bitches, most neoplasms with a histopathological grade III occurred in animals older than 10 years, in agreement with the literature. Age increasing might be related to more biologically aggressive mammary gland tumours. Early neutering is commonly recommended to prevent proliferative abnormalities in the mammary glands, but it has been related to several disorders, and neoplasms, in some breeds. Multiple tumours in more than one mammary gland with different histopathological diagnoses among them, isn’t related to multicentric disease or worse prognosis, as also seen in this survey.Among mammary glands, the inguinal and caudal abdominal are often the most affected,as it was observed in this study; however, no differences were observed in the occurrence of malignant neoplasms, benign or non-neoplastic

Solid Iridociliary Carcinoma in a Dog

Background: Iridociliary epithelial tumors (ICETs) originate from the iris epithelium or ciliary body. They comprise ciliary body adenoma, carcinoma, pleomorphic adenocarcinomas, medulloepitheliomas, and other primitive neuroectodermal tumors. They are the second most common primary intraocular tumors in dogs and have already been reported in sheep and humans. In dogs, they occur more frequently in middle-aged to elderly animals, and the Labrador and Golden Retriever seem to be more predisposed breeds. This study aimed to describe the clinical and pathological aspects of solid iridociliary carcinoma in a dog. Case: A 3-year-old Poodle bitch was treated for discomfort in the left eyeball region, increased intraocular pressure and moderate buphthalmia. A direct ophthalmological examination was performed without equipment, and a mass was visualized in the posterior chamber, distorting the pupillary cleft. We opted for unilateral enucleation and forwarded the material for histological analysis. Macroscopically, the eyeball measured 3.4 cm (anteroposterior) x 2.6 cm (vertical), with a brownish mass that occupied the entire anterior chamber and part of the posterior chamber. Histologically, there was a neoformation in the ciliary body and iris pigment epithelium, partially well-delimited and densely cellular. The neoplasm was organized into predominantly solid formations interspersed with a discrete amount of blood vessels, rare bundles of fibrous stroma, and amorphous eosinophilic material forming membranes that were positive for PAS. Sections of the neoplasm were subjected to immunohistochemistry using anti-cytokeratin AE1/AE3, anti-S100 protein, anti-vimentin, and anti-Ki-67. Positive cytoplasmic immunostaining for cytokeratin and S-100 was observed. Only 45.6% of cells were positive for Ki-67 (500 cells). No immunostaining was observed for vimentin. Discussion: The diagnosis of solid iridociliary carcinoma was based on the histological features and positive immunostaining for cytokeratin AE1/AE3 and protein S100. Iridociliary carcinomas present positive immunostaining for cytokeratin, whereas adenomas and normal iridociliary epithelium do not present this immunostaining. Moreover, the high rate of cell proliferation was indicative of malignant neoplasia, as observed by the high mitotic count and high positivity for Ki-67. The S100 protein helped in the diagnosis of ICETs, as the iridociliary epithelium showed positive staining for this protein. Some histological features are important to consider in the diagnosis of iridociliary tumors in dogs, such as noninvasive growth in the posterior chamber, pigment epithelium, and thick homogeneous membranes on the cell surface. Furthermore, the presence of positive PAS membranes favors the diagnosis of iridociliary epithelial tumors. ICETs must be differentiated from melanocytomas, anterior uveal melanoma, medulloepitheliomas, and metastatic and pleomorphic carcinomas. The histological characteristics, especially the presence of PAS-positive membranes, associated with the immunohistochemical profile of neoplasm cells, help differentiate the ICETs from these tumors. In general, the prognosis is poor for eyeball and vision maintenance in canine iridociliary tumors, and scleral invasion is associated with a higher recurrence rate.   Keywords: neoplasm, eye, immunohistochemistry, cytokeratin, S100 protein

Abortion in Captive Gray Brocket Deer (Mazama gouazoubira) Associated with Colloid Goiter, Hemonchosis and Necrotizing Rumenitis

Background: The gray brocket deer (Mazama gouazoubira) is a specie that shows great adaptability in different habitats and it is the most abundant deer specie in South America. The present work describes for the first time a case of abortion followed by death associated with colloid goiter, massive hemonchosis and necrotizing rumenitis in a captive female gray brocket deer. Case: A 4-year-old female gray brocket deer (M. gouazoubira) raised in captivity had a history of abortion during the last third of gestation. The animal was kept in an enclosure together with 3 other gray brockets deers, being 1 male of the same age and 2 juvenile brocket deer of approximately 1 and 2 years old. The animals were fed with concentrated used as cattle feed and dewormed annually with 1% Ivermectin. The animals' enclosure had vegetation cover formed by grasses and soil. The animals appeared healthy with no behavioral changes. The day after the stillbirth, the mother was found dead in the enclosure and sent to the animal pathology sector of the University of Vila Velha (UVV), Brazil. Necropsy revealed that thyroid lobules were highly increased in volume and histopathological findings were compatible with colloid goiter. A large number of nematodes were found in the abomasal content,totalizing 11,626 helminths, which were morphologically characterized as Haemonchus contortus. Grossly, the serous and ruminal mucosa exhibited an extensively reddish focal area with irregular contour, surface ulceration and a firm consistency. Microscopically, a severe necrotizing rumenitis was diagnosed. The liver showed pale multifocal areas on the subcapsular surface,friable to the touch which deepened when cut. Histopathological analysis revealed an accentuated multifocal panlobular coagulative necrosis, characterizing an acute liver necrosis.Discussion: Iodine is a mineral of great importance for thyroid hormones synthesis and your requirements are higher during pregnancy and lactation. Diets deficient in iodine causes a reduction in the basal activity of the hormones triiodothyronine (T3) and thyroxine (T4) and over-stimulation of the thyroid by thyroid stimulating hormone (TSH), resulting in goiter. In the present case, it is possible that the shortage of iodine in diet caused a goiter and, as a consequence, triggered the abortion. Haemonchus contortus is a pathogenic nematode of small ruminants, leading to decreased productivity and death in some cases as a result of anemia and hypoxia. The contact between domestic and wild animals, resulting in the emergence of infectious diseases and the spread of pathogens among species. In the present case, manual counting accounted for 11,626 H. contortus larvae, characterizing a massive infection and justifying the condition of severe anemia. The high parasitic load shown in this case points out this parasite's importance related to this species in captivity. In general, inflammatory lesions in the rumen are results of excessive intake of fermentable carbohydrates, which leads to a considerable decrease in ruminal pH and leads to a high proliferation of lactic acid bacteria. This lesion has been previously reported in cervids. This case of comorbidities demonstrates that failures in nutritional and health handling, may cause simultaneous multiple diseases leading to death. Preventive measures for helminth parasite control and a proper feeding management with an adequate diet must be provided in order to preserve the species in captivity. Keywords: colloid goiter, abortion, cervids, Haemonchus contortus

Cytological and Histopathological Correlation of Feline Giant Cell-Rich Osteosarcoma

Background: Primary bone tumours are uncommon and poorly reported in cats but osteosarcoma (OSA) is the most frequent, mostly in elderly animals. Giant cell-rich OSA is considered rare in the literature representing 3% of all OSA in humans. The mitotic index seems to have a significant effect on the survival time of cats affected by this neoplasm as well as the tumour histopathological grade. The objective of this study was to report the cytological and histopathological findings of a giant cell rich OSA in a 4-year old cat with persistent feline leukemia virus (FeLV) antigenaemia.Case: A 4-year-old male neutered cat was referred with a history of persistent FeLV viraemia and pelvic limb lameness with a firm swelling. Previous radiographs of the affected limb revealed bone lysis in the third and fourth metatarsals and increased soft tissue radiopacity in the tarsal region. The referral veterinary assumed it to be osteomyelitis and initiated clinical treatment with antibiotic and anti-inflammatory. The cat was referred after there was no response to medical treatment. The cat was presented with a 5cm diameter ulcerated mass, with putrid odor in the pelvic limb. Complementary exams were performed, and abnormalities were found, including increased urea, creatinine, calcium and potassium, and decreased sodium and phosphorus. A new radiograph showed exuberant bone proliferation, with increased radiopacity involving tarsal, metatarsal, distal third of tarsal I and II, and distal diaphysis of metatarsal V, without compromising the metaphyseal region of distal diaphysis of metatarsal IV. Chest radiographs and abdominal ultrasound were unremarkable. Fine-needle aspiration was performed for cytological analysis, which reavealed a moderate amount of pleomorphic mesenchymal cells with moderate adhesion, cytoplasm with a format ranging from fusiform to stellate, pronounced anisocytosis and cellular pleomorphism, and elevated nucleus:cytoplasm ratio. Nucleus was oval and presented loose chromatin, single to double large and evident nucleolus, frequent karyomegaly, along with marked anisocariosis and nuclear pleomorphism. Multinucleated giant cells were and there was a single mitotic figure in 12 high power fields (0.196 mm2 FN20/400x). Therefore, it was suggestive of malignant mesenchymal neoplasia with possibility of OSA, fibrosarcoma oe undifferentiated sarcoma. Limb amputation with femoral disarticulation was performed uneventfully. The material was conserved in 10% formalin, submitted to macroscopic and microscopic evaluation, which showed a large number of fusiform and stellate cells, with indistinct edges, scarce eosinophilic cytoplasm, high nucleus:cytoplasm ratio and oval nucleus, presenting moderate to marked anisocariosis, loose chromatin, with unique and evident nucleoli, besides of bone trabeculae. Nuclear pleomorphism was moderate and there was four mitotic figures in three random high-power fields (400x). It was observed areas of vascular ectasia, and neoplastic embolization in lymphatic and blood vessels. Among the cells, collagenous stroma was predominant but in some areas there was an eosinophilic amorphous material with the possibility of osteoid matrix or collagen. There was also a large numbers of multinucleated giant cells. The histopathological result was compatible with a grade III giant cell rich OSA.Discussion: Although bone tumours are uncommon in cats, OSA is the most frequent, affecting maingly middle-aged to elderly cats, with a mean age of 10 years, which is different from the present report in a 4-year old cat, with FeLV persistent viraemia. Retroviral status may have influenced the development of the disease at na early onset. FeLV induces uncontrolled cell proliferation through insertional mutagenesis (usually near myc) inducing malignant neoplasias, mainly lymphoma, but also multiple cartilaginous exostosis, which, along with osteomyelitis and bone cyst were included in this patient´s list of differential diagnoses. Despite the macroscopic and radiographical andagressiveness there was no metastasis identified through chest radiographs or abdominal ultrasound, and feline OSA is associated with a lower metastatic rate, if compared to canine OSA. Cytological analysis was compatible with malignant mesenchymal neoplasia, being suggestive of giant cell rich OSA. There is no cytological classification for OSA, however cytological findings of malignancy may be correlated with the patient's clinical course. Cytological features were in agreement with the histopathological findings, compatible with a grade III giant cell rich OSA. Therefore, it is concluded that the characteristics of malignancy presented by cytology were sufficient for the recommendation of amputation of the affected limb, once there was no imaging sign of metastases in the chest or abdomen

Secretory carcinoma of the canine mammary gland with nodal and bone metastases: Case report

Background: Secretory carcinoma is a rare histological type of breast neoplasm in humans and dogs that is characterized by the presence of intracellular and extracellular eosinophilic secretions.Case Description: In this case report, we describe the cytological, histological, and immunohistochemical characteristics of secretory mammary carcinoma in a 10-year-old mixed-breed female dog with nodal and bone metastases. The bitch had a history of claudication and a mass in the left humeral scapular region, which revealed osteolysis of the proximal humerus on radiography. Fine-needle aspiration cytology revealed numerous neoplastic cells arranged mostly in cohesive groups but sometimes isolated, that contained cytoplasmic vacuoles and had a moderate-to-high nucleus: cytoplasm ratio with frequent karyomegaly and evident nucleoli. Histologically, the neoplasm was organized in solid, tubular structures with luminal spaces filled with eosinophilic secretions and was composed of cells with clear cytoplasm and prominent vacuoles that pushed the nuclei to the periphery, resembling signet ring cells. The extracellular and intracytoplasmic material of the epithelial cells was positive for periodic acid-Schiff staining and immunoreactive for alpha-lactalbumin. Two chemotherapy sessions were performed, but 1 month after surgery, the clinical condition worsened, and euthanasia was elected, accounting for 133 days of survival after surgical removal of the tumor.Conclusion: The bitch presented with secretory mammary carcinoma with nodal and bone metastases, and histological and immunohistochemical characteristics were important for diagnosis. The morphological and immunohistochemical characteristics of this carcinoma were similar to those observed in humans. Mammary gland secretory carcinoma with bone metastasis must be included as a differential diagnosis among canine mammary gland carcinomas showing cellular morphological characteristics of intracytoplasmic vacuolization and eosinophilic secretion